全文获取类型
收费全文 | 3085篇 |
免费 | 188篇 |
国内免费 | 147篇 |
专业分类
耳鼻咽喉 | 21篇 |
儿科学 | 135篇 |
妇产科学 | 97篇 |
基础医学 | 344篇 |
口腔科学 | 59篇 |
临床医学 | 347篇 |
内科学 | 718篇 |
皮肤病学 | 81篇 |
神经病学 | 254篇 |
特种医学 | 399篇 |
外科学 | 344篇 |
综合类 | 35篇 |
预防医学 | 177篇 |
眼科学 | 65篇 |
药学 | 191篇 |
1篇 | |
中国医学 | 3篇 |
肿瘤学 | 149篇 |
出版年
2022年 | 15篇 |
2021年 | 36篇 |
2020年 | 24篇 |
2019年 | 46篇 |
2018年 | 39篇 |
2017年 | 45篇 |
2016年 | 32篇 |
2015年 | 67篇 |
2014年 | 54篇 |
2013年 | 112篇 |
2012年 | 126篇 |
2011年 | 131篇 |
2010年 | 98篇 |
2009年 | 111篇 |
2008年 | 119篇 |
2007年 | 199篇 |
2006年 | 117篇 |
2005年 | 122篇 |
2004年 | 89篇 |
2003年 | 80篇 |
2002年 | 77篇 |
2001年 | 76篇 |
2000年 | 73篇 |
1999年 | 75篇 |
1998年 | 104篇 |
1997年 | 94篇 |
1996年 | 86篇 |
1995年 | 73篇 |
1994年 | 53篇 |
1993年 | 61篇 |
1992年 | 51篇 |
1991年 | 60篇 |
1990年 | 54篇 |
1989年 | 84篇 |
1988年 | 70篇 |
1987年 | 72篇 |
1986年 | 55篇 |
1985年 | 50篇 |
1984年 | 36篇 |
1983年 | 33篇 |
1982年 | 39篇 |
1981年 | 26篇 |
1980年 | 27篇 |
1979年 | 39篇 |
1978年 | 27篇 |
1977年 | 34篇 |
1976年 | 40篇 |
1975年 | 31篇 |
1974年 | 16篇 |
1971年 | 17篇 |
排序方式: 共有3420条查询结果,搜索用时 78 毫秒
81.
Glucose tolerance and B cell function in chronic alcoholism: its relation to hepatic histology and exocrine pancreatic function 总被引:1,自引:0,他引:1
B N Andersen C Hagen O K Faber J Lindholm P Boisen H Worning 《Metabolism: clinical and experimental》1983,32(11):1029-1032
Glucose tolerance and B cell function were assessed in 30 consecutive chronic alcoholic patients without overt diabetes mellitus. Plasma glucose, insulin, and C peptide concentrations were measured during an oral glucose tolerance test. All patients underwent a liver biopsy and an exocrine pancreatic function test (Lundh test). Compared with the controls, the three groups of alcoholic patients (those with histologically normal livers, n = 12; those with steatosis, n = 10; and those with cirrhosis, n = 8) all had a two-fold increase in plasma concentrations of insulin as well as C peptide in the fasting state, despite normal fasting levels of glucose. After oral glucose all groups of patients had elevated plasma levels of glucose, insulin, and C peptide compared with the controls. The C peptide/insulin ratio was similar to that in the controls in all groups of alcoholics. Patients with decreased exocrine pancreatic function (n = 7) had a significantly lower insulin and C peptide response to glucose than the patients with normal exocrine pancreatic function. It is concluded that (1) chronic alcoholics even with histologically normal livers have endogenous insulin resistance, and (2) associated damage to the exocrine pancreas is more common than previously recognized and decompensation of B cell function could be demonstrated in patients with decreased exocrine pancreatic secretion. 相似文献
82.
Immunohistochemical localization of membrane and alpha-granule proteins in human megakaryocytes: application to plastic-embedded bone marrow biopsy specimens 总被引:12,自引:2,他引:12
Using a new technique for antigen localization, we have demonstrated platelet proteins in megakaryocytes in plastic-embedded biopsy specimens of normal human bone marrow. In a series of 25 specimens, megakaryocytes showed labeling with antibodies to the integral membrane glycoproteins IIIa, IIb, and the IIb-IIIa complex; granule membrane protein 140; and five alpha-granule matrix proteins: thrombospondin, factor VIII-related antigen, beta-thromboglobulin, platelet factor 4, and fibrinogen. The antibodies to the membrane glycoproteins IIIa, IIb, and IIb-IIIa produced diffuse cytoplasmic staining and heavier staining on the plasma membrane, whereas the antibodies to the alpha-granule matrix proteins produced a distinct granular staining within the cytoplasm. Staining for granule membrane protein 140 was also granular in distribution. Rare mononuclear cells consistent with megakaryocyte precursors were labeled with these markers. Other enzyme histochemical and lectin-binding studies showed that the enzyme alpha-naphthyl acetate esterase, the lectin Ulex europaeus I, and the periodic-acid Schiff reaction were consistent, but not specific, markers of megakaryocytes. This immunohistochemical technique should facilitate the examination of qualitative and quantitative changes in megakaryocytes in a variety of physiologic and pathologic processes. 相似文献
83.
Kralisch S Sommer G Stangl V Köhler U Kratzsch J Stepan H Faber R Schubert A Lössner U Vietzke A Bluher M Stumvoll M Fasshauer M 《Atherosclerosis》2008,196(2):523-531
Hyperplasia and hypertrophy of fat cells can be found in obesity, and increased adiposity is associated with endothelial dysfunction as an early event of atherosclerosis. However, it is unclear whether human adipocytes directly influence endothelial function. To study the crosstalk between fat and endothelial cells, human umbilical venous endothelial cells (HUVECs), and human coronary artery endothelial cells (HCAECs) were cultured in infranatants (Adipo) of primary differentiated human adipocytes. Interestingly, incubation of HUVECs and HCAECs with Adipo significantly increased monocyte adhesion 7.3 and 2.2-fold, respectively. VCAM-1, ICAM-1, and E-selectin in HUVECs were upregulated 3.9, 3.0, and 9.5-fold, respectively, under these conditions. Furthermore, Adipo significantly stimulated NFkappaB activity 1.9-fold. The NFkappaB inhibitor MG-132 and heat inactivation significantly reversed Adipo-stimulated monocyte adhesion. TNFalpha-neutralizing antibodies partly reversed Adipo-induced monocyte adhesion. In contrast, thiazolidinedione-pretreatment of human adipocytes did not alter the effects of Adipo. Adipo did not show cytotoxic effects. Taken together, we demonstrate that endothelial dysfunction is induced by adipocyte-secreted factors via NFkappaB partly dependent on TNFalpha. 相似文献
84.
Thomas W Baron Thomas S Faber Andreas Grom Tillmann Schwab Michael Brunner Annette Geibel Hanj?rg Just Christoph Bode Manfred Zehender 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2006,8(11):994-1001
AIM: In the presence of coronary artery disease, implantable cardioverter-defibrillators (ICD) are used effectively for treating life-threatening tachyarrhythmias. Continuous monitoring of myocardial ischaemia would provide a new diagnostic option in future ICD generations. METHODS AND RESULTS: In 22 selected patients undergoing coronary angioplasty, percutaneous transluminal coronary angioplasty (PTCA), three electrodes, similar to those used in the ICD, were inserted aiming to create six intra-thoracic ECG (IT-ECG) leads according to Einthoven and Goldberger. In total, 27 PTCA were conducted. The diagnostic efficacy for ischaemia assessment was compared with the surface ECG. The IT-ECG proved to be more sensitive than conventional ECG in early and overall ischaemia assessment. At 30 s of coronary artery occlusion, ischaemic ST-segment alterations (> or =0.25 mV) were present in the IT-ECG 2.3 times more often (23 vs. 10/27 PTCA attempts, P<0.01) and at 90 s 1.4 times more often compared with conventional ECG leads (18 vs. 26/27, P<0.05). Intra-thoracic Einthoven 2 (SVC+RVA vs. ICD-housing) and Goldberger 3 (SVC+ICD-housing vs. RVA) had the highest sensitivity (88/85%). Using > or =4 IT-ECG, ischaemia monitoring was independent of severity and site of origin. IT-ECG signals showed double ST-T signal amplitude (4.19+/-0.6 vs. 2.15+/-0.3 mV, ratio: 1.95, P<0.01) at a QRS/ST amplitude ratio similar in the two ECG techniques. CONCLUSION: This study provides strong evidence that the ICD-based IT 6-lead ECG would provide a new and efficient means of assessing a patient's daily ischaemic burden. 相似文献
85.
Activated protein C resistance: molecular mechanisms based on studies using purified Gln506-factor V 总被引:6,自引:1,他引:6
Gln506-factor V (FV) was purified from plasma of an individual homozygous for an Arg506Gln mutation in FV that is associated with activated protein C (APC) resistance. Purified Gln506-FV, as well as Gln506-FVa generated by either thrombin or FXa, conveyed APC resistance to FV-deficient plasma in coagulation assays. Clotting assay studies also suggested that APC resistance does not involve any abnormality in FV-APC-cofactor activity. In purified reaction mixtures, Gln506-FVa in comparison to normal FVa showed reduced susceptibility to APC, because it was inactivated approximately 10-fold slower than normal Arg506-FVa. It was previously reported that inactivation of normal FVa by APC involves an initial cleavage at Arg506 followed by phospholipid- dependent cleavage at Arg306. Immunoblot and amino acid sequence analyses showed that the 102-kD heavy chain of Gln506-FVa was cleaved at Arg306 during inactivation by APC in a phospholipid-dependent reaction. This reduced but measurable susceptibility of Gln506-FVa to APC inactivation may help explain why APC resistance is a mild risk factor for thrombosis because APC can inactivate both normal FVa and variant Gln506-FVa. In summary, this study shows that purified Gln506- FV can account for APC resistance of plasma because Gln506-FVa, whether generated by thrombin or FXa, is relatively resistant to APC. 相似文献
86.
Stuart W. Grande Marjan J. Faber Marie-Anne Durand Rachel Thompson Glyn Elwyn 《Patient education and counseling》2014
Objective
Examine existing reviews of patient engagement methods to propose a model where the focus is on engaging patients in clinical workflows, and to assess the feasibility of advocated patient engagement methods.Methods
A literature search of reviews of patient engagement methods was conducted. Included reviews were peer-reviewed, written in English, and focused on methods that targeted patients or patient–provider dyads. Methods were categorized to propose a conceptual model. The feasibility of methods was assessed using an adapted rating system.Results
We observed that we could categorize patient engagement methods based on information provision, patient activation, and patient–provider collaboration. Methods could be divided by high and low feasibility, predicated on the extent of extra work required by the patient or clinical system. Methods that have good fit with existing workflows and that require proportional amounts of work by patients are likely to be the most feasible.Conclusion
Implementation of patient engagement methods is likely to depend on finding a “sweet-spot” where demands required by patients generate improved knowledge and motivate active participation.Practice implications
Attention should be given to those interventions and methods that advocate feasibility with patients, providers, and organizational workflows. 相似文献87.
Svenja Sydor Paul Manka Lea van Buren Sarah Theurer Suzan Schwertheim Jan Best Janette Heegsma Ali Saeed Diana Vetter Martin Schlattjan Anna Dittrich Maria I. Fiel Hideo A. Baba Alexander Dechêne Francisco J. Cubero Guido Gerken Ali Canbay Han Moshage Scott L. Friedman Klaas Nico Faber Lars P. Bechmann 《Liver international》2020,40(9):2172-2181
88.
89.
90.
Zhenwu Lin John P. Hegarty Wei Yu Jon A. Cappel Xi Chen Pieter W. Faber Yunhua Wang Lisa S. Poritz Jian-Bing Fan Walter A. Koltun 《Digestive diseases and sciences》2012,57(12):3145-3153